European Union antitrust regulators have received new proposals from Google as it tries to avoid a huge fine and to settle a three-year row over how it presents search results.

The EU competition chief, Joaquín Almunia, said at the weekend that he would decide on the proposals in the coming months, but would probably put it to "market testing", in which rivals would get a say on its approval or rejection.

If no deal can be reached, the European commission could fine Google up to 10% of its revenues, and impose its own ruling on how Google presents its own and others' sites in search results.

Its aim is to ensure Google's monopoly in search is not used to shut out rivals in different fields. Google previously offered to make some alterations to how it shows search results – a proposal that other companies roundly rejected in July.

Separately, Almunia's team has told Samsung Electronics to offer new concessions in an antitrust investigation over its use of "standards-essential" patents in lawsuits against Apple last year.

The EC aims to stop Samsung from trying to shut out rivals by refusing to licence the patents, which are needed in modern smartphones. Doing so breaches the pledges made by the company to standards bodies.

If Samsung does not satisfy the EC it could be fined 10% of its 2012 worldwide revenue – which would amount to $18.3bn (£11.6bn) , the largest fine ever imposed by the EC. The present record is €1.47bn (£1.24bn) imposed in December over a cartel in TV parts, against eight firms including Samsung, Philips, LG and Toshiba.

"The commission can confirm that Samsung has submitted proposals, the commission has assessed them and asked Samsung to improve them," Jonathan Todd, an EU spokesman, said.